conterm/posix-mips/tas.s

22 lines
377 B
ArmAsm

#include <sys/regdef.h>
#include <sys/asm.h>
.globl tas
.ent tas 2
tas:
.set noreorder
1:
ori t1, zero, 12345 /* t1 = 12345 */
ll t0, (a0) /* t0 = *a0 */
sc t1, (a0) /* *a0 = t1 if *a0 hasn't changed; t1=success */
beq t1, zero, 1b /* repeat if *a0 did change */
nop
j $31 /* return */
or v0, t0, zero /* set return value on way out */
.set reorder
.end tas